I also thought of the whole nuclear energy thing. The dilemma between unsafe energy and negative headlines in the sixties (and thus the mentality that lots of people still have) vs. possibilities to cut the emission of greenhouse gases.

You could study our greed culture and whether it is ethical to increase the rate of productivity in energy production without at the same time increasing the distribution of profits to those doing the work. In other words, as productivity and efficiency has increased, profits have increased for the companies, but wages have nearly stagnated for the workforce.

There was a report in Tech-on about how the economic collapse and several other factors such as Spanish over-investment led to massive price drops in silicon PVs and how this might push PVs over the "grid-parity" brink. It is a really good read. I suggest at least glancing through the figures.